1. Field of the Invention
The present invention relates to a projector, and in particular to a projector disposed in a portable electronic apparatus.
2. Description of the Related Art
MEMS technology is applied in many common apparatus or electronic products. The DMD (Digital Micro-mirror Device) produced by TEXAS INSTRUMENTS is a reflection device used in projection apparatus. The technology applied in DMD is DLP (Digital Light Processing). The DMD comprises many micro-mirrors, arrayed in a grid, each reflecting a light beam to form a pixel on a projection plate. The DLP has a three-color light source (red, green, and blue) which emits three colored light beams. The color light beams contact the micro-mirrors alternatingly, controlling the number of light beams reflected to the projection plate to represent the brightness and color of pixels, composing a complete full-color image.
Conventionally, the DMD is used in overhead projectors. However, since the DMD is a small device, it can be applied to a portable electronic apparatus like mobile phones or PDA, providing a small, convenient portable projector.
However, even though pixels may be dark, the projection light source emits the same quantity of light for each, despite the micro-mirror not reflecting the light to the projection plate. Thus, energy is wasted. Projectors utilizing DMD technology, if applied in a portable electronic apparatus, use excessive energy, creating a serious problem.